PROBESE
Trial question
What is the effect of an intraoperative mechanical ventilation strategy with a higher level of PEEP and alveolar recruitment maneuvers in obese patients undergoing surgery under general anesthesia?
Study design
Multi-center
Open label
RCT
Population
Characteristics of study participants
70.0% female
30.0% male
N = 1976
1976 patients (1381 female, 595 male).
Inclusion criteria: adult patients with body mass indices ≥ 35 and substantial risk for postoperative pulmonary complications who were undergoing noncardiac, nonneurological surgery under general anesthesia.
Key exclusion criteria: previous lung surgery, receipt of invasive mechanical ventilation for > 30 minutes within the last 30 days, receipt of chemotherapy or radiotherapy within 2 months.
Interventions
N=989 high level of PEEP (a PEEP level of 12 cmH₂O with alveolar recruitment maneuvers performed after endotracheal intubation).
N=987 low level of PEEP (a PEEP level of 4 cmH₂O).
Primary outcome
Rate of postoperative pulmonary complications within the first 5 days
21.3%
23.6%
23.6 %
17.7 %
11.8 %
5.9 %
0.0 %
High level of
PEEP
Low level of
PEEP
No significant
difference ↔
No significant difference in the rate of postoperative pulmonary complications within the first 5 days (21.3% vs. 23.6%; RR 0.93, 95% CI 0.83 to 1.04).
Secondary outcomes
Significant decrease in hypoxemia (5% vs. 13.6%; RR 0.51, 95% CI 0.4 to 0.65).
No significant difference in postoperative extrapulmonary complications (16.9% vs. 15.2%; RR 1.06, 95% CI 0.95 to 1.19).
No significant difference in systemic inflammatory response syndrome (9.4% vs. 8.4%; RR 1.06, 95% CI 0.91 to 1.22).
Safety outcomes
No significant differences in death during the hospital stay, DIC, coma, hepatic failure, extrapulmonary infection, septic shock, severe sepsis.
Significant differences in hypotension (31.6% vs. 17.2%), bradycardia (9.9% vs. 6.0%).
Conclusion
In adult patients with body mass indices ≥ 35 and substantial risk for postoperative pulmonary complications who were undergoing noncardiac, nonneurological surgery under general anesthesia, high level of PEEP was not superior to low level of PEEP with respect to the rate of postoperative pulmonary complications within the first 5 days.
Reference
Writing Committee for the PROBESE Collaborative Group of the PROtective VEntilation Network (PROVEnet) for the Clinical Trial Network of the European Society of Anaesthesiology, Thomas Bluth, Ary Serpa Neto et al. Effect of Intraoperative High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers vs Low PEEP on Postoperative Pulmonary Complications in Obese Patients: A Randomized Clinical Trial. JAMA. 2019 Jun 18;321(23):2292-2305.
Open reference URL